Earthcorp Restoration Work, October 2012

EarthCorps Restoration Work, October 2012
By T. Richard Leary and Steve Johnston


Various Reserve Committee members started talking about EarthCorps just a few years ago.  In a Reserve Committee meeting late last spring Innis Arden resident and owner of Seattle Tree Preservation John Hushagen strongly recommended that we contact EarthCorps to see if they could work for us to help manage our invasive plants issues in the Innis Arden Natural Reserves.  We met with EarthCorps representatives Jamie Kingham, Field Operations Manager, and Rob Anderson, Senior Project Manager, and showed them what the issues were from Bear Reserve through Eagle Reserve.

Bear Reserve was logged in early 2011 restoring views that had been lost by a number of residents for many years.  This allowed a lot of sunlight to reach the ground level.  An irrigation system was also installed by the Bear Reserve Group to support the 144 trees and approximately 3000 shrubs and ground cover that were planted in the spring of 2011.  The higher intensity of light, the water, and consequent warming of the soil during the summer caused Bindweed (morning glory), Blackberry, and Buttercup to proliferate uncontrolled.  Thus, while solving a view issue we created an invasive plant issue due to dormant seeds now sprouting abundantly. 

We worked with Rob Anderson to create maps of the various types of invasive plants that infest our reserves, such as Himalayan Blackberry, English Laurel, English Holly, Butterfly Bush, Japanese Knotweed, English Ivy, Yellow Buttercup, Yellow Archangel, and, of course, English Ivy.  One example of Himalayan Blackberry Map for Blue Heron and Eagle Reserves is provided below.  These maps will serve as a reference so that in the future we can perform another survey and compare with the 2012 maps.   This way we can get a relative measure of where we are making progress and where we still need more work.

EarthCorps began its work on October 9th in Bear Reserve concentrating on English Laurel, Bindweed, Himalayan Blackberry, and Buttercup.  They then moved down to Running Water Reserve and Blue Heron Reserve where the majority of the work was performed.  Removing the Ivy from the trees at the West end of Running Water and the West end of Blue Heron (Zone 1) reserves should help save trees and will keep the climbing Ivy from going to seed and spreading further via birds eating its berries.  The Laurel infestations in both reserves (not to mention Bear reserve) will be greatly reduced due to the many herbicide pellet injections into the stems.  The hand-grubbing of other invasive plants will also make a visible difference.

Click on map to enlarge

 In Blue Heron the first zone begins along the creek at the trail entrance of Springdale Road and extends along the creek and trail to mid-Blue Heron. The second area is just before the switchback, along the hillside covered with sword-fern above the trail and adjacent to zone 5.  The third area is in mid-Blue Heron, on the far side of the creek from the trail, on the hillside near zone 2. These areas are in one of the most natural and beautiful parts of the Blue Heron reserve.

The reserve committee members were pleased to observe how much of the area the crew was able to grub through and to inject with herbicide pellets.  We also appreciate the way the crew ‘policed’ the western edge of the large bank of Ivy above the trail in the ‘containment zone’ covering the hill just after the switchback on the way downhill in the Blue Heron central area.

The EarthCorps personnel are trained to work effectively on invasive plants removal and have the equipment needed to accomplish their job.  Here’s a summary of the work completed by the EarthCorps crew 10/9 through 10/19:  The crew completed a total of 244 person-hours of work on the ground. 

Preparing an Ivy ring

Bear Reserve:

  • Knotweed injected/sprayed: approx. 875 square feet
  • Bindweed (Morning Glory) removed from native plants, larger blackberry grubbed: approx. 9,000 square feet
  • Bindweed/blackberry/other weeds sprayed with herbicide: approx. 6,800 square feet.
  • Invasive trees injected with herbicide capsules: 57 stems, average diameter of 6.5 inches.
  • Smaller invasive tree sprouts were pulled and/or cut and stump treated with herbicide.

In summary the entirety of this site was treated at some level and looks greatly improved. The invasive trees should start to die back by early to the middle of November, including the bindweed. We expect that Bear Reserve will need maintenance again next year with bindweed, blackberry and knotweed re-growth but hopefully on a significantly smaller scale than this year’s growth.

Grouse/Running Water/Blue Heron Reserves (combined total for these tasks)

  • Survival rings completed (Ivy removed around base of native trees): 74 trees
  • Invasive Laurels and Holly injected with herbicide capsules: 280 stems, average diameter of 3.75 inches.

Many of the smaller invasive trees were pulled and/or cut and stump treated with herbicide. Note that many smaller invasive trees still remain as well as significant Blackberry and Ivy areas.

Blue Heron Reserve (Central Area)

In Blue Heron, we have now established and maintained for the first time some native, invasive plant-free zones near the middle of the reserve.  Ground Ivy and other invasive plants were removed in an area of approximately 8,300 square feet.  Invasive trees were also treated throughout this area (numbers included in the totals listed previously) to create our “demonstration” area free of invasive plants. The trail separating central from further down into the reserve provides a good before/after picture of the process of invasive removal.

Much more work needs to be done to expand this protected zones.  The Reserves Committee needs to annually establish and police these containment zone(s).  But overall, we are off to an impressive start in our struggle to manage the Innis Arden natural reserves.